Rotator system including a remote drive motor and a local indicator-control motor

ABSTRACT

A remotely controlled shaft rotator is described wherein a local indicator-control device is driven by a regulated local reversible motor. The local motor is initially responsive to a pulse derived at the remote drive unit for driving the indicatorcontrol device a given amount as controlled by a cam operated switch.

United States Patent [111 3,860,859 Buckley l l Jan. 14, 1975 ROTATOR SYSTEM INCLUDING A 3,102.218 8/l963 DlCkC 3lX/4l REMOTE DRIVE MOTOR AND A LOCAL 3,200,3l4 8/1965 lrolcr Mil/265 X INDICATOR-CONTROL MOTOR Inventor: Bruce Harry Buckley, Huntingdon Valley, Pa.

Assignce: RCA Corporation, New York, NY.

Filed: July 24, 1972 Appl. N0.: 274,638

U.S. Cl 318/265, 318/41, 318/673 Int. Cl. G05d 3/00 Field of Search 318/41, 265267,

References Cited UNITED STATES PATENTS 2/1950 McNaney 318/673 Primary h'.\'umincrRobcrt K. Schacfcr Assistant ExaminerW. E. Duncunson, Jr.

Attorney, Agent, or FirmEdward J. Norton; Robert L. Troike A remotely controlled shaft rotator is described wherein a local indicator-control device is driven by a regulated local reversible motor. The local motor is initially responsive to a pulse derived at the remote drive unit for driving the indicator-control device a given amount as controlled by a cam operated switch.

ABSTRACT 9 Claims, 4 Drawing Figures l REVOLUTION SYNCHRONIZER 55 MEMORY CAM 87 ROTATOR SYSTEM INCLUDING A REMOTE DRIVE MOTOR AND A LOCAL INDICATOR-CONTROL MOTOR This invention relates to a rotator system and particularly to the use of a controlled, reversible electric motor in a rotator system to drive an indicator-control device that both indicates position of a remote rotating shaft and automatically deactivates the system when at l a preselected position.

In antenna rotators, for example, it is desirable to remotely preselect and to indicate the direction that an antenna is pointing. One way of achieving this is by means of a synchro system, Le, a system of a generator and a motor where the rotor of a motor aligns itself with the fields of a stator winding. Such a synchro system is costly and therefore is generally considered as being undesirable as a rotator for home television antenna systems, FM receiving antennas, etc.

Another technique for indicating antenna direction is by the pulsed energization of a solenoid which causes either the stepping of a ratchet wheel (see US. Pat. No. 3,501,969) or allows the movement of a spring driven escapement wheel one notch or tooth per movement of the solenoid. These ratcheting and eseapement systems are noisy and sometimes require a pair of solenoids unless a specific structure is used to provide bidirectional movement. Further it is desirable to preselect the desired antenna direction and to use the same system for both indicating the pointing direction of the antenna and for automatically stopping the antenna at a preselected direction.

Briefly, according to the present invention a system is provided for rotating a remote shaft relative to a support and for providing an indication of the position of the shaft. A first reversible drive unit includes a first reversible motor and a first drive train by which the first motor when energized drives the first drive train and a shaft. A local movable indicator is coupled to a second drive unit including a second reversible motor and a second drive train. The second reversible motor in response to energizing potential drives the second drive train and the indicator. A first switching means is coupled between a suitable source of potential and the first motor to operate the first motor to provide shaft rotation and movement of the first drive train. A second switching means is coupled between a suitable source of potential and the second motor and is further responsive to each given movement of the first drive train to cause activation of the second motor. A motor control means is responsive to the movement of the second drive train to control the energization potentials and the rotation of the second motor and the movement of the indicator coupled thereto.

DETAILED DESCRIPTION A more detailed description follows in conjunction with the accompanying drawing wherein:

FIG. 1 is a schematic diagram of a rotator system according to the present invention;

FIG. 2 is a top plan view of the control unit of the antenna rotator system without connecting wires and transformer;

FIG. 3 is an elevation view of the local control unit of FIG. 2 as viewed in the direction of line 33; and

FIG. 4 is a perspective view of the direction-memory cam according to an embodiment of the present invention.

Referring to FIG. 1, a rotator system 10 includes a shaft rotator, remote drive unit 11, a local control unit 13 and four wires 15, 16, 17 and 19 interconnecting the control unit 13 and the remote drive unit 11. The control unit 13 may be located on top of a television set, and the drive unit 11 may be located at a remote posi- 0 tion such as at an antenna mast supported from and extending above the roof top of a dwelling.

At the input to the control unit 13 is a transformer 21 which in response to 1]? volts AC at the primary 23 provides 20 volts AC at the secondary 25. A main, onoff switch 27 is coupled in series with the primary 23 of transformer 21. When the contacts 27a and 27b of switch 27 are closed, the 1 17 volts AC is applied across the primary 23 and coupled to the secondary 25 of transformer 21. 1f the contacts 27a and 27b are open, the transformer 21 and consequently the overall system 10 is de-energized.

The opening and closing of contacts 27a and 27b is provided by misalignment and alignment, respectively, of a preselector disk 54 (shown in more detail in FIGS. 2 and 3) and an indicator disk 53. For purposes of illustration, disks 53 and 54 are shown in simplified form in FIG. 1 and are tilted slightly so disk 54 can be seen. A more detailed description of this structure is discussed below in connection with FIGS. 2 and 3. Briefly, however, when a knob 81 is rotated clockwise or counterclockwise, the disk 54 that is mechanically coupled thereto is rotated clockwise or counterclockwise. Switch 27 which may be coupled to disk 54 turns with disk 54. The indicator-control disk 53 is spaced parallel to and above preselector disk 54 on a shaft 83 (see FIG. 3). Disk 53 is mounted so as to freely rotate on the shaft. Disk 53 has an extension 84 thereon adapted so that when the disks 53 and 54 are aligned, an extension 84 pushes contact 27a away from contact 27b, deenergizing the system. When extension 84 is misaligned with switch 27, as when knob 81 rotates the disk 54 clockwise or counterclockwise, the contacts 270 and 27b being free of the extension 84 are closed and the system is energized.

The remote drive unit 11 includes an AC motor 31. The drive unit motor 31 includes a pair of windings 31a and 31b. Coupled to the drive unit motor 31 is a gear train 33 (partially shown) and a rotatable shaft 35. An antenna mast (not shown) may be fixed to the rotatable shaft 35. The shaft 35 and the mast is driven via the gear train 33 by drive unit motor 31. One end 25a of secondary winding 25 is coupled by wire 16 to one end 32 of AC motor windings 31a and 31b. The opposite end of the motor winding 31a is coupled over wire 19 to a terminal 41 of motor direction switch 43. The opposite end of motor winding 31b is coupled by wire 17 to a second terminal 42 of motor direction switch 43. A phase shifting capacitor 37 is coupled between wires 17 and 19 for providing phase shift therebetween and providing activation of the motor 31. The other end 25b of secondary winding 25 is coupled to the center terminal 44 of motor direction switch 43.

Motor direction switch 43 is a flexible leaf contact switch with a flexible contact member 44a connected to terminal 44 and adapted, when flexed, to make contact with either contact member 42a connected to terminal 42 or with contact member 41a connected to terminal 41. When member 44a makes contact with member 41a, the drive unit motor 31 rotates clockwise for example, with the current going through wire 19 and winding 31a via contacts 44a and 41a. When contact member 44a is closed with contact member 42a, the drive unit motor 31 rotates in the opposite or counterclockwise direction with currents coupled via contact members 44a and 42a along wire 17 to winding 31b.

The motor direction switch 43 is, for example, fixed to disk 54. Also fixed to the disk 54 is a directionmemory cam 87. The cam 87 is rotatably mounted to the disk 54 and has an extension that fits into a groove 89 in disk 53 when disks 53 and 54 are aligned. As shown in FIGS. '2 and 3, the cam 87 has gaps 102 and 104 therein. Flexible leaf contact 44a extends into gap 104. When knob 81 rotates clockwise, the directionmemory cam 87 rotates counterclockwise and causes direction-memory cam 87 to push contact 44a into connection with contact 410. When knob 81 rotates counterclockwise, the direction-memory cam 87 rotates clockwise and causes contact 44a to connect with contact 42a. A more detailed discussion of this cam 87 and the disks 53 and 54 is provided in connection with FIGS. 2 thru 4.

A local indication of the rotated position of the remotely located rotating shaft and hence the pointing direction of the antenna is provided by a pulsing circuit at the drive unit 11, a DC control unit motor 51, a syn chronizer cam 55, the indicator-control disk 53, a pair of rectifier diodes 65 and 67 and a pair of control switches 61 and 71. At the drive unit 11 is located an intermittent switch 47. The intermittent switch 47 has one terminal 48 connected to wire 16 and the other terminal 49 connected to one end 51a of the DC control unit motor 51. The switch 47 has a pair of contacts 48a and 49a which are normally open. Associated with the gear train 33 of motor 31 is a cam 45 which has a high point 45a which when driven by the drive unit motor 31 through the gear train 33 intermittently provides contact between contacts 49a and 48a of switch 47. The'result is a pulse output and an energizing source of potential from switch 47 that is coupled by wire to DC control unit motor 51.

The direction in which the DC control unit motor 51 turns is determined by the position of switch 61. The switch 61 is fixed, for example, to disk 54 with a center contact member 66a positioned in gap 102 of the direction-memory cam 87. A first terminal 68 of switch 61 is coupled to the anode of diode 67. The cathode of diode 67 is coupled to end 25b of secondary 25. Terminal 64 of switch 61 is coupled to the cathode of diode 65. The anode end of diode 65 is coupled to the end 25b of secondary 25. Diodes 65 and 67 each provide half wave rectification of the AC signal at the secondary 25.

Since diodes 6S and 67 are oppositely connected, current direction and DC control unit motor rotation direction is controlled by which of terminals 64 or 68 completes the circuit through the DC control unit motor 51. The center leaf contact member 66a can make contact with either member 68a or 64a. Contact member 68a is connected with terminal 68, and contact member 64a is connected with terminal 64. The flexible contact member 66a is connected to terminal 66, and terminal 66 is coupled by wire 69 to terminal 51b of DC control unit motor 51. When knob 81 is rotated clockwise, cam 87 is rotated counterclockwise, causing center flexible leaf contact member 66a to make contact with member 64a. The 20 volt AC is then half wave rectified by diode 65, and the DC current is coupled through contacts 64a and 66a and wire 69 to control unit motor 51, resulting in the control unit motor 51' rotating in a first direction. When knob 81 is rotated counterclockwise, cam 87 is rotated clockwise causing flexible contact 660 to make contact with member 68a. In this position the 20 volts AC is half wave rectified with current flowing through diode 67. contact members 66a and 68a, wire 69 and through control unit motor 51 to drive motor 51 in the other direction.

The DC control unit motor 51 is coupled by a gear train 52 to indicator-control disk 53 and to a synchronizing cam 55. The synchronizing cam 55 has a raised or camming region 55a and a low or off region 55b. A synchronizing switch 71 having a center flexible leaf contact member 72a, a contact member 73a and a contact member 74a is provided for controlling the DC control unit motor 51. Terminal 72 of switch 71 is connected to center flexible member 72a. Terminal 74 of switch 71 is connected through switch 71 to contact member 74a, and terminal 73 is connected through switch 71 to contact member 73a. Terminal 74 is connected to wire 69 and end terminal 51b of DC control unit motor 51. Terminal 73 is connected by wire 103 to wire 16. Terminal 72 is coupled through 27 ohm resistor 101 and bypass charge capacitor microfarad) to terminal 51a of motor 51. The synchronizing cam 55 is positioned relative to the flexible leaf contact member 72a so that when the raised region 550 is in contact with the member 72a, this member 72a makes contact with member 74a. When cam 55 is in position to present the low or off the cam portion 55b, contact member 72a which is spring loaded or otherwise biased, makes contact with contact member 73a.

In the operation of the above described indicating portion of the remote control system 10, drive unit cam 45 makes one revolution for every 6 of rotation of the drive unit shaft 35. Similarly, synchronizing cam 55 is geared to make one revolution for every 6 turn by the indicator-control disk 53.- The same ratio of turns that exists between drive unit cam 45 and the antenna shaft 35 (60 to 1) exists between the revolution synchronizer cam 55 and indicator-control disk 53. When the drive unit motor 31 rotates the cam 45 to close the contacts 48a and 49a at high point 45a, a pulse is coupled to control unit motor 51 which initially energizes control unit motor 51. Control unit motor 51 turns in response to the direction indicated by switch 61 so that synchronizing cam 55 is rotated from presenting its high or raised portion 55a to switch 71 to its low (or off the cam) position 55b. Whencontact member 720 of switch 71 is off the cam or presenting its low position 55b, switch member 720 makes contact with member 73a keeping the DC control unit motor 51 energized through the resistor-capacitor combination 101 and 105, contact member 72a, contact member 73a and wire 103 to a connection at wire 16. When the synchronizer cam 55 is driven by the control unit motor 51 and gear train 52 to present the raised portion 5511, member 72a breaks contact with member 73a and makes contact with member 74a to de-energize the control unit motor 51. Motor resistor 101 and charging capacitor 105 operate to prevent the DC control unit motor from overdriving the high or raised portion 55a of the synchronizing cam 55. Capacitor 105 charges against the direction of current through DC control unit motor 51 and resistor 101 acts as an additional load resistor in series with the DC control unit motor 51.

The speed of the DC control unit motor 51 is such that the synchronizer cam 55 turns faster than drive unit cam 45. Control cam 55 is driven faster by DC motor 51 than is the cam 45 by the motor 31 so that cam member 55 turns one complete revolution and indicator-control disk 53 progresses 6 before the cam member 45 is able to make a second connection of members 48a and 49a at switch 47 and before shaft 35 and the antenna has rotated 6. DC control unit motor 51 and cam member 55 then wait for another pulse from the drive unit 11. The resynchronization at 6 intervals by energizing the DC control unit motor 51, rotating the cam 55 one revolution and shutting off the motor continues for each pulse applied from the drive unit 11 until the selected position is reached, wherein the drive unit 11 is de-energized and the main on-off switch 27 is in the off or open position. This resynchronization at 6 intervals of the two motors ensures that the antenna or remote rotator is kept in alignment with the control unit despite variations in the drive motor speed due to variable loading on the antenna drive motor 31.

Referring to FIGS. 2, 3 and 4, there is shown a top view and an elevation view respectively of the control unit 13 which includes the indicator-control disk 53 positioned in a given alignment above the disk 54. The control knob 81 is coupled to a shaft 83 which extends through indicator-control disk 53 and is fixed to selector disk 54. Indicator-control disk 53 is mounted to shaft 83 so that it freely rotates about the shaft. Selector disk 54 is fixedly mounted and rotates with the shaft. The shaft 83 is fixed but rotatably mounted to a baseboard 85. Extending between selector disk 54 and indicator-control disk 53 is the leaf spring type, normally closed contact switch 27. A small member 84 extends from a point near the periphery of control disk 53 and only makes contact with normally closed on-off switch 27 when disks 53 and 54 are in aligned position therewith to break the contact between the members 27a and 27b, deactivating the system 10. g

The motor direction switches 61 and 43 are mounted to selector disk 54. The rotatable direction-memory cam 87 is rotatably mounted to the selector disk 54 by a pin 88a having a head below disk 54 and extending through disk 54 and base portion 95. Referring to H6. 4, the direction-memory cam 87 includes a base portion 95 adapted to receive pin 88a and three parallel extending members 96, 97 and 98 spaced from each other and from the base portion 95 by spacer portion 99. A tooth shaped member 88 extends vertically and laterally from the base member 95. A gap 104 exists between members 98 and 97, and a gap 102 exists between members 97 and 96. The rotatable directionmemory cam 87 extends in the region between indicator-control disk 53 and disk 54 with the tooth-shaped extending member 88 positioned just below control disk 53. A ring member 53a positioned below indicator-control disk 53 may be formedas an extension of disk 53 so as to extend about the periphery of this disk.

The ring member 53a has a groove 89 therein extending from the inboard surface. The tooth-shaped member 88 of direction-memory cam 87 is adapted to fit into groove 89 when the control disk 53 and selector disk 54 are aligned and the main on-off switch 27 is deenergized.

The direction-memory cam 87 and the switches are arranged so that flexible leaf member 44a extends through gap 104 and flexible leaf member 66a extends through gap 102. See FIGS. 2 and 4. When the control disk 53 and the disk 54 are aligned, the tooth-shaped member 88 is lodged into slot 89 and the flexible contact members 66a and 44a make no contact with either of their adjacent contact members. When the control knob 81 and disk 54 is rotated, for example, in a clockwise direction, the tooth-shaped member 88 is driven laterally and thereby rotates out of slot 89 and causes the direction-memory cam 87 to rotate, in the example, in a counterclockwise direction. When direction-memory cam 87 rotates in a counterclockwise direction, the member 98 of direction-memory cam 87 pushes contact member 44a and member 97 of direction-memory cam 87 pushes contact member 66a so that contact member 44a makes contact with member 41a and contact member 66a makes contact with member 64a. The drive unit 11 is then made to rotate in the selected direction with the DC control motor 51 made to drive the control disk 53 in the proper direction in response to impulses from the drive unit 11 to realign disk 53 with disk 54.

When the DC motor 51 drives disk 53 back to the aligned position with disk 54, the tooth-shaped member 88 is again in slot 89 of disk 53 centering the contact members 66a and 44a. When the control knob 81 is rotated in the opposite direction, counterclockwise, direction-memory cam 87 is rotated in a clockwise direction, with the member 44a making contact with member 42a and member 66a making contact with associated contact member 68a. The operation will be as described above.

What is claimed is:

l. A system for rotating a remote shaft and for providing a local indication of the rotated position comprising:

a first driving means including a first reversible motor and a first drive train, said first reversible motor being responsive to energization potential applied thereto for driving said remote shaft and said first drive train,

a local movable indicator,

a second driving means including a second reversible motor and a second drive train coupled to each other and said indicator and responsive to an energization potential applied thereto for driving said indicator,

first switching means coupled between a suitable source of potential and said first motor for causing rotation of said shaft and movement of said first drive train,

second switching means including a first cam and a first cam-operated switch driven by said first cam coupled between a suitable source of potential and said second motor and coupled to said first drive train responsive to a given movement of said first drive train to cause activation and rotation of said second motor and movement of said indicator,

motor control means including a second cam and a second cam-operated switch driven by said second cam coupled to said second drive train for controlling the rotation of said second motor to provide a predetermined movement of said indicator each time said first drive train moves said given amount.

2. The combination as claimed in claim I, wherein said second cam-operated switch is a single pole double throw switch with the movable arms thereof being driven by said second cam.

3. The combination as claimed in claim 1, wherein said second motor rotates at sufficiently higher speedthan said first motor so that said second reversible motor has provided said predetermined movement of said indicator before the first motor has moved said first drive train another of said given amount.

4. A system for rotating a remote shaft and for providing a local indication of the rotated position thereof comprising: 7

a first driving means including a first reversible motor and a first gear train, said first reversible motor being responsive to energization potential applied thereto for driving said remote shaft and gear train,

first switching means coupled between a suitable source of potential for said first motor and said first motor for causing rotation of said shaft and movement of said first gear train,

a local movable indicator,

a second driving means including a second reversible motor and a second gear train coupled to each other and said indicator and responsive to an energizing potential applied thereto .for driving said indicator,

interrupting switch means coupled between a suitable source of potential for said second motor and said second motor and coupled to said first gear train for in response to a given movement of said first gear train causing momentary activation and rotation of said second motor and movement of said indicator,

a cam coupled to said second gear train,

motor control switch means driven by said cam and coupled between said suitable source of potential for said second motor and said second motor and responsive to momentary activation of said cam for operating said second motor to provide a predetermined movement of said second gear train.

5. The combination as claimed in claim 4, wherein said interrupting switch means includes a cam and a cam operated switch with said cam being driven by said first gear train and said switch being coupled between said suitable source of potential for said second motor and said second motor.

6. A system for automatically rotating a remote shaft to which an antenna may be coupled to a preselected position comprising in combination:

a first driving means including a first motor having reversing means, said first driving means coupled to said remote shaft for causing rotation thereof,

a second driving means including a second motor having reversing means,

means by which said first and second driving means can be energized,

means coupled to said first driving means and said energization means for providing an energizing signal potential for said second motor each time said remote shaft turns a given amount,

a movable preselector member,

- an indicator-control member driven by said second driving means and movably mounted relative to said preselector member,

a first switching means coupled between said energization means and said first driving means in a manner to cause when in a first switch position said first driving means to rotate said shaft in a first direction or in a second switch position said first driving means to rotate said shaft in a second opposite direction,

a second switch means coupled between said energization means and said second driving means in a manner to cause when in a first switch position said second driving means to drive said indicatorcontrol member in a first direction or in a second switch position said second driving means to drive said indicator-control member in a second reverse direction,

said first and second switch means being coupled to a third switch means coupled to said members and said energization means for de-energizing said first and second motors only upon alignment of said disks.

8. A system for automatically rotating a remote shaft to which an antenna may be coupled to a preselected position comprising in combination:

a first driving means includinga first motor having reversing means, said driving means coupled to said remote shaft for causing rotation thereof,

a second driving means including a second motor having reversing means,

means by which said first and second driving means can be energized,

means coupled to said first driving means and to said energization means for providing an energization potential for said second motor each time said remote shaft rotates a given amount in a selected direction,

a movable preselector disk and an indicator-control disk, said indicator-control disk having a groove therein at a point near the periphery of said disk,

a first single pole double throw switch having a flexible contact member coupled to said energization means and centered between two relatively fixed contact members with a first of said fixed contact members coupled to said first motor in a manner to cause said first motor to rotate in a first direction and with the second of the fixed contact members coupled to said first motor in a manner to cause said first motor to rotate in a reverse direction,

a second single pole double throw switch having a flexible contact member coupled to said energization means and centered between two relatively fixed contact members with the first of said fixed contact members of said second switch coupled to said second motor in a manner to cause when said second switch is in a first position said second motor to rotate in a first direction and with the second of the fixed contact members of the second switch coupled to said second motor in a manner to cause when said second switch is in a second position said second motor to rotate in a reverse direction,

a direction-memory cam having a pair of apertures therein adapted to receive said flexible contact members,

said direction-memory cam being rotatably mounted said first switch being arranged with the center flexible contact member thereof extending into one aperture of said direction-memory cam to cause, when said preselector disk moves with respect to said indicator-control disk in a first non-aligned direetion, said flexible contact member thereof to contact said first fixed contact member of said first switch causing said first motor to rotate in said first direction and to cause, when said preselector disk moves with respect to said indicator-control disk in a second non-aligned direction said flexible contact member to contact said second fixed contact member thereof causing said first motor to rotate in said reverse direction,

said second switch being arranged with the center flexible contact member extending into the second aperture of said direction-memory cam to cause, when said preselector disk moves with respect to said indicator disk in said first non-aligned direction, the flexible contact member of the second switch to contact with said first fixed contact member thereof causing said second motor to rotate said indicator disk in said first direction unless said disks are aligned and to cause, when said preselector disk moves with respect to said indicator disk in said second non-aligned direction, said flexible contact member of the second switch to contact said second fixed contact member thereof causing said second motor to rotate said indicator disk in said reverse direction unless said disks are aligned.

9. The combination as claimed in claim 8, wherein said second motor is a DC motor and said reversing means for said second motor includes a pair of diodes wherein said first fixed contact member of said second switch is coupled to a first diode poled in one sense and said second fixed contact member of said second switch is coupled to the second diode poled in an opposite sense.

UNITED STATES PATENT OFFICE (IERTIFICATE OF CORRECTION PATENT NO. 3, 860, 859

DATED 1 January 14, 1975 INVENTOR(S) Bruce Harry Buckley It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

0n the page containing the abstract, after "Filed:

July 24, 1972", insert Foreign Priority Application British Provisional Application No.

47310/71, October 11, 1971 Signed and Scaled this fourteenth Day of October 1975 [SEAL] A ttes t:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner ufPatents and Trademarks UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. s, 860, 859

DAT I January 14, 1975 INVENTORiS) Bruce Harry Buckley It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On the page containing the abstract, after "Filed:

July 24, 1972" insert Foreign Priority Application British Provisional Application No.

47310/71, October 11, 1971 Signed and Scaled this fourteenth Day Of October 1975 [SEAL] Arrest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner ofParents and Trademarks 

1. A system for rotating a remote shaft and for providing a local indication of the rotated position comprising: a first driving means including a first reversible motor and a first drive train, said first reversible motor being responsive to energization potential applied thereto for driving said remote shaft and said first drive train, a local movable indicator, a second driving means including a second reversible motor and a second drive train coupled to each other and said indicator and responsive to an energization potential applied thereto for driving said indicator, first switching means coupled between a suitable source of potential and said first motor for causing rotation of said shaft and movement of said first drive train, second switching means including a first cam and a first camoperated switch driven by said first cam coupled between a suitable source of potential and said second motor and coupled to said first drive train responsive to a given movement of said first drive train to cause activation and rotation of said second motor and movement of said indicator, motor control means including a second cam and a second camoperated switch driven by said second cam coupled to said second drive train for controlling the rotation of said second motor to provide a predetermined movement of said indicator each time said first drive train moves said given amount.
 2. The combination as claimed in claim 1, wherein said second cam-operated switch is a single pole double throw switch with the movable arms thereof being driven by said second cam.
 3. The combination as claimed in claim 1, wherein said second motor rotates at sufficiently higher speed than said first motor so that said second reversible motor has provided said predetermined movement of said indicator before the first motor has moved said first drive train another of said given amount.
 4. A system for rotating a remote shaft and for providing a local indication of the rotated position thereof comprising: a first driving means including a first reversible motor and a first gear train, said first reversible motor being responsive to energization potential applied thereto for driving said remote shaft and gear train, first switching means coupled between a suitable source of potential for said first motor and said first motor for causing rotation of said shaft and movement of said first gear train, a local movable indicator, a second driving means including a second reversible motor and a second gear train coupled to each other and said indicator and responsive to an energizing potential applied thereto for driving said indicator, interrupting switch means coupled between a suitable source of potential for said second motor and said second motor and coupled to said first gear train for in response to a given movement of said first gear train causing momentary activation and rotation of said second motor and movement of said indicator, a cam coupled to said second gear train, motor control switch means driven by said cam and coupled between said suitable source of potential for said second motor and said second motor and responsive to momentary activation of said cam for operating said second motor to provide a predetermined movement of said second gear train.
 5. The combination as claimed in claim 4, wHerein said interrupting switch means includes a cam and a cam operated switch with said cam being driven by said first gear train and said switch being coupled between said suitable source of potential for said second motor and said second motor.
 6. A system for automatically rotating a remote shaft to which an antenna may be coupled to a preselected position comprising in combination: a first driving means including a first motor having reversing means, said first driving means coupled to said remote shaft for causing rotation thereof, a second driving means including a second motor having reversing means, means by which said first and second driving means can be energized, means coupled to said first driving means and said energization means for providing an energizing signal potential for said second motor each time said remote shaft turns a given amount, a movable preselector member, an indicator-control member driven by said second driving means and movably mounted relative to said preselector member, a first switching means coupled between said energization means and said first driving means in a manner to cause when in a first switch position said first driving means to rotate said shaft in a first direction or in a second switch position said first driving means to rotate said shaft in a second opposite direction, a second switch means coupled between said energization means and said second driving means in a manner to cause when in a first switch position said second driving means to drive said indicator-control member in a first direction or in a second switch position said second driving means to drive said indicator-control member in a second reverse direction, said first and second switch means being coupled to said movable preselector member and said indicator-control member so that misalignment of said members in one sense causes rotation of said first and second reversible motors in one direction and misalignment of said members in a second sense causes rotation of said first and second reversible motors in a second sense.
 7. The combination as claimed in claim 6, including a third switch means coupled to said members and said energization means for de-energizing said first and second motors only upon alignment of said disks.
 8. A system for automatically rotating a remote shaft to which an antenna may be coupled to a preselected position comprising in combination: a first driving means including a first motor having reversing means, said driving means coupled to said remote shaft for causing rotation thereof, a second driving means including a second motor having reversing means, means by which said first and second driving means can be energized, means coupled to said first driving means and to said energization means for providing an energization potential for said second motor each time said remote shaft rotates a given amount in a selected direction, a movable preselector disk and an indicator-control disk, said indicator-control disk having a groove therein at a point near the periphery of said disk, a first single pole double throw switch having a flexible contact member coupled to said energization means and centered between two relatively fixed contact members with a first of said fixed contact members coupled to said first motor in a manner to cause said first motor to rotate in a first direction and with the second of the fixed contact members coupled to said first motor in a manner to cause said first motor to rotate in a reverse direction, a second single pole double throw switch having a flexible contact member coupled to said energization means and centered between two relatively fixed contact members with the first of said fixed contact members of said second switch coupled to said second motor in a manner to cause when said second switch is in a first position said second motor to rotate in a first direction and with the second of the fixed contact members of the second switch coupled to said second motor in a manner to cause when said second switch is in a second position said second motor to rotate in a reverse direction, a direction-memory cam having a pair of apertures therein adapted to receive said flexible contact members, said direction-memory cam being rotatably mounted to said preselector disk with said direction-memory cam extending between said preselector disk and said indicator-control disk with an extended portion of said cam fitting into said groove located in said indicator-control disk when said preselector disk and said indicator-control disk are in their aligned position, said first switch being arranged with the center flexible contact member thereof extending into one aperture of said direction-memory cam to cause, when said preselector disk moves with respect to said indicator-control disk in a first non-aligned direction, said flexible contact member thereof to contact said first fixed contact member of said first switch causing said first motor to rotate in said first direction and to cause, when said preselector disk moves with respect to said indicator-control disk in a second non-aligned direction said flexible contact member to contact said second fixed contact member thereof causing said first motor to rotate in said reverse direction, said second switch being arranged with the center flexible contact member extending into the second aperture of said direction-memory cam to cause, when said preselector disk moves with respect to said indicator disk in said first non-aligned direction, the flexible contact member of the second switch to contact with said first fixed contact member thereof causing said second motor to rotate said indicator disk in said first direction unless said disks are aligned and to cause, when said preselector disk moves with respect to said indicator disk in said second non-aligned direction, said flexible contact member of the second switch to contact said second fixed contact member thereof causing said second motor to rotate said indicator disk in said reverse direction unless said disks are aligned.
 9. The combination as claimed in claim 8, wherein said second motor is a DC motor and said reversing means for said second motor includes a pair of diodes wherein said first fixed contact member of said second switch is coupled to a first diode poled in one sense and said second fixed contact member of said second switch is coupled to the second diode poled in an opposite sense. 